Stock-Based Compensation (Tables)

9 Months Ended

Feb. 28, 2015

Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan

The following table summarizes the Company’s total stock-based compensation expense recognized in Operating overhead expense:



	Three Months Ended February 28,				Nine Months Ended February 28,
(In millions)	2015		2014		2015		2014
Stock options⁽¹⁾	$	35	$	32	$	100	$	93
ESPPs	5		5		17		16
Restricted stock	8		6		23		22
TOTAL STOCK-BASED COMPENSATION EXPENSE	$	48	$	43	$	140	$	131

(1)

Expense for stock options includes the expense associated with stock appreciation rights. Accelerated stock option expense is recorded for employees eligible for accelerated stock option vesting upon retirement. Accelerated stock option expense for the three month periods ended February 28, 2015 and 2014 was $5 million and $3 million, respectively, and for the nine month periods ended February 28, 2015 and 2014 was $14 million and $11 million, respectively.

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The weighted average assumptions used to estimate these fair values are as follows:



	Nine Months Ended February 28,
	2015		2014
Dividend yield	1.2	%	1.3	%
Expected volatility	23.6	%	27.9	%
Weighted average expected life (in years)	5.8		5.3
Risk-free interest rate	1.7	%	1.3	%